Real Betis expected Tottenham to sign Giovani Lo Celso on a permanent basis in January.
The midfielder arrived last summer on a loan deal, with Spurs given the option to make the move permanent for €32million next month of €40 in the summer.
Real Betis president Angel Haro, speaking at a meeting of the club’s shareholders, admitted that Spurs are likely to complete the signing.
He said: “[Tottenham] will exercise it because if they don’t they will be [charged more] in June.
“They may also have to exercise the mandatory [clause].
“We understand that they will exercise it, but if not [we will be] delighted with the player [returning].”